wondering whats different between Standard Public and Standard terminal wlan?If there are same or somewhat similar then can you swap the tests and see if there is any difference?which firmware version in use? which model of ZD?Did you enable roaming related features on the controller that "may" help?

Also, I don't know I'm I able to compare relatively new Android and Windows CE 6.0 (basically launched 2006) devices... The device itselt (barcode scanner) is brand new device, but the OS is quite old..

i would suggest some more stuff to try on both sides, client and controller to see if that makes a different:

1. play with roaming aggressiveness on the terminals.2. enable Fast BSS roaming, I am seeing this feature on 9.8.0.0 build 1725 so please chk ur controller.3. try to put same channel on both AP's n try the test again to see if it helps...